Artykuły (CN-jcme)

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Artykuły czasopisma Journal of Casting & Materials Engineering

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Access status: Open Access ,
Calculation of assimilation process of non-metallic inclusions by slag
(AGH University of Science and Technology Press, 2017) Kalisz, Dorota
This paper presents the results of calculating the phenomenon of the absorption of non-metallic precipitates in steel by slag. Calculations are made for the forces acting on the non-metallic particles in steel during the flow-out into the slag, depending on the particle radius and physicochemical properties of the liquid steel and slag. An analysis of the calculation results of capillary force acting on a particle in the vicinity of the steel-slag interface at changing surface energy values between the precipitates and slag shows that capillary force depends on the interfacial tension between the precipitates and slag only to a small degree.
Access status: Open Access ,
Optimization of a gating system by means of simulation software to eliminate cold shut defects in casting
(AGH University of Science and Technology Press, 2021) Šabík, Vladimír; Futáš, Peter; Pribulová, Alena; Delimanová, Petra
The current trend in foundries is to achieve the production of high quality and competitive cast components. The innovation and optimization of current processes is a necessary element to achieve this goal. With the help of numerical simulations, it is possible to replace financially demanding and time-consuming experiments in real conditions with simulations that can reliably represent foundry process using computer technology. By a detailed analysis of the simulation results, we can predict various risks that could negatively affect the production process. This article monitors the influence of changes in the design of the gating system on the surface quality of a clutch wheel casting made of ductile iron, in the production of which two models of the gating system for casting were constructed in CAD software. Verification of gating systems was performed using the simulation software NovaFlow & Solid. The aim of the design change of the gating system is to reduce the amount of liquid metal used per casting, which can have a significant economic impact on industrial production. For this purpose, several simulations of the gating system of the casting were performed, while 2 which are the most representative for the mentioned problem were selected for the needs of the article. The main task of the simulation was to set the cellular network and conditions as close as possible to the reality of casting and the subsequent design and modification of the gating system.
Access status: Open Access ,
Artificial neural networks as a tool for supporting a moulding sand control system based on the dependency between selected moulding sand properties
(AGH University Press, 2023) Mrzygłód, Barbara; Jakubski, Jarosław; Opaliński, Andrzej; Regulski, Krzysztof
The article presents the potential for using artificial neural networks to support decisions related to the rebonding of green moulding sand. The basic properties of the moulding sand tested in foundries are discussed, especially compactibility as it gives the most information about the quality of green moulding sand. First, the data that can predict the compactibility value without the need for testing are defined. Next, a method for constructing an artificial neural network is presented and the network model which produced the best results is analysed. Additionally, two applications were designed to allow the investigation results to be searchable by determining the range of values of the moulding sand parameters.
Access status: Open Access ,
Etching method to create random speckle pattern on semi-solid cast A356 aluminium for DIC in-situ strain measurement
(2017) Sergolle, Maëlle; Santos, Jorge; Kasvayee, Keivan Amiri; Jarfors, Anders Eric Wollmar
Aluminum semi-solid casting is constantly evolving, as it offers a combination of reduced shrinkage porosity and gas entrapment defects together with high productivity and an extended die-life. The relationship between the microstructure and stress-strain behavior is not well-understood due to its non-conventional microstructure. In-situ tensile testing, combined with optical microscope and Digital Image Correlation (DIC), has been used for local strain distribution measuements in cast irons. The critical capability was an etching technique to generate a micro-scale random speckle pattern with a sufficiently high speckle density to enable the sufficient spatial resolution of displacement and strain. The current paper focuses on the development of a pit etching procedure for the semi-solid cast A356 aluminum alloy to study local strain accommodation on the microstructure during tensile loading. The critical challenge of this procedure was the generation of homogeneously distributed pits on both the primary aluminum and eutectic regions. Therefore, a heated solution used for wet-etch aluminum in microfabrication was modified as well as a process adapted to generate pits with suitable characteristics. In-situ tensile tests were performed attached to an optical microscope to record the microstructure and displacements during loading. DIC software was used for analysis. The procedure was validated through a comparison between the resulting Young´s moduls using standard tensile testing and the DIC process on the speckle pattern generated. A good fit between the two methods for Young´s modulus was found. The spatial resolution obtained was, however, not sufficient to fully resolve the strain gradients in the microstructure, but it did reveal large strain variations in the microstructure.
Access status: Open Access ,
Polylactide Used as Filament in 3D Printing – Part 2: TG-DTG, DSC and DRIFT Investigations
(AGH University Press, 2023) Grabowska, Beata; Skowron, Mateusz; Kaczmarska, Karolina
In this second part of the article, we delve deeper into the research area initiated in the first part, focusing on the critical exploration of polylactide (PLA) modification to enhance thermal and mechanical properties in PLA-based materials, building upon the insights obtained from comprehensive structural and thermal analyses utilizing analytical methods such as infrared spectroscopy (FTIR), diffuse reflectance infrared spectroscopy (DRIFT), and thermoanalytical research (DRIFT, TG-DTG). A series of structural and thermal analysis research (TG-DTG, DSC, DRIFT) were performed for samples of polylactide (PLA), which is commonly used in additive technologies as a structural material. In total, four materials were considered, including two containing dyes with different colors, a material made of PLA recyclate and a graphene-modified PLA material. It was noted that PLA material reinforced with graphene phase (GRAFYLON®) retains the best thermal properties (TG-DTG), which results in its wider potential for processing, including further modification and usability in manufacturing vehicle structural elements. Recycled PLA material (ALFA+W) was characterized by a higher melting point (T$_{p}$) by more than 20°C than other samples (DSC analysis), so it can be more useful in the production of structural elements operating and used at elevated temperatures.
Access status: Open Access ,
An Analysis of Transient States in the Power Supply System of a Selected Industrial Robot
(AGH University Press, 2025) Nowocień, Sebastian; Ziółkowski, Eugeniusz
Industrial robots are controlled by dedicated controllers powered by a single-phase or three-phase power supply system. The main power parameters characterizing the power supply system of these robots are: nominal supply voltage (1-phase: 100–120 V, 200–240 V or 3-phase 200–575 V AC), frequency of the supply voltage (50 Hz or 60 Hz), the nominal power consumed by industrial robot. The dynamics of power consumption in the power supply system of the controlled robot can be studied by recording instan¬taneous values of voltages and currents in each phase of the power grid. In this article, results are presented for the measurements of mentioned instantaneous values for a chosen single-phase powered robot, taken by specialized recorder. The measurements obtained from the recorder allows the calculation of numerically various energetic values in the power supply system of the robot: peak-peak values, RMS values, coefficients of deformation and values of harmonic amplitudes (FFT), values of active, reactive and apparent power and the power coefficient (tg?). The analysis of the waveforms of the instantaneous values of voltage and current allows the determination of the occurrence of transient states during the work of robot axes and characterizing its duration and the range of value changes. The analyses conducted can be used to properly design the protection systems of the power supply system, the eventual selection of filters for higher harmonics, and to determine the effective power consumption of the studied robot. The analyses of the transient states which occurred during the work of the studied robot in this publication significantly expand the knowledge about the dynamics of power consumption and its possible impact on the quality of electricity in the power supply grid.
Access status: Open Access ,
Mechanical and thermal properties of graphene over composite materials: a technical review
(AGH University of Science and Technology Press, 2019) Islam, Md Mashrur; Ahmed, Sadman Saffaf; Rashid, Moshiur; Akanda, Md Masum
The recent years have seen numerous developments in the research and headway of graphene, the thinnest two-dimensional nuclear material. Graphene-based materials and their composites have promising applications in an extensive variety of fields, for example, gadgets, biomedical guides, films, adaptable wearable sensors, and actuators. The most recent investigations and movement in this branch of knowledge regularly deliver conflicting or uncertain outcomes. This article evaluates and outlines the distributed information in order to give a basic and complete diagram of the cutting edge. Initially, the particular basic nature of accessible graphene materials is illustrated as well as the distinctive generation methods accessible thus far. The appraisal at that point talks about the different composites that center diverse sub-practical routines, for example, mechanical and aggregate utilitarian applications (e.g., vitality, hardware biomedical, layers, and sensors). The use of graphene and its subsidiaries in the fabricate of nanocomposites with various polymer frameworks has been inspected. And finally, an ending and point of view are given to talking about the rest of the difficulties for graphene nanocomposites in useful science and building.
Access status: Open Access ,
Influence of selected corrosive environment on the scale formation in selected materials manufactured by directed energy deposition 3D printing technology
(AGH University Press, 2025) Małysza, Marcin; Rząd, Ewa; Zięba, Łukasz
Additive technologies, and in particular Directed Energy Deposition (DED), are becoming an increasingly important tool for the rapid production of components operating in, among others, the energy, aviation, petrochemical industries, where components are exposed to extreme thermochemical conditions. In the article, the influence of various corrosive atmospheres atmospheric air, water vapor and SO?-argon- mixture – on the process of scale formation on the surface of materials manufactured using Directed Energy Deposition (DED) technology is presented. The tests were carried out at a temperature of 600°C (for air and water vapor) and 300°C (for SO?-argon atmosphere). The mass increase and surface damage was monitored. It has been shown that the chemical composition of materials, especially the content of alloying elements such as Cr and Ni, is crucial for corrosion resistance. The obtained results provide the basis for further optimization of the composition of powders used in additive man ufacturing techniques, in terms of operating conditions in aggressive environments.
Access status: Open Access ,
Microstructural characterization and mechanical behavior of copper matrix composites reinforced by B4C and sea shell powder
(AGH University of Science and Technology Press, 2018) Sankar, Mathiazhagan; Pushpanathan, D. Peter; Myszka, Dawid; Devaneyan, Pradeep S.
This paper investigates the microstructural and mechanical properties of copper metal matrix composites reinforced with B$_{4}$C and crushed sea shell particles (fabricated using powder metallurgy). In powder form, copper is widely used in structural applications. Copper also possesses very good electrical and thermal conductivity, ductility, and corrosion resistance. B$_{4}$C is the third-hardest-known material that also possesses excellent toughness and wear resistance. Sea shells are readily available along coastal areas. Therefore, an attempt has been made in this work to investigate the feasibility of its utilization in powder metallurgy. Two batches of samples were prepared. In the first batch, the percentage of boron carbide and copper powder were varied, and seashell powder was not included. In the second batch, the percentages of B$_{4}$C, copper, and sea shell powder were varied in order to assess the change effected by the sea shell material. The sintered samples of both batches were subjected to microstructural characterization to ascertain the homogeneous distribution of the reinforcements. The microhardness and wear resistance of all of the fabricated samples were assessed. The results confirmed that the inclusion of 2% sea shell powder (by weight) with 10% boron carbide improved the wear resistance and hardness of the composite.
Access status: Open Access ,
The Influence of Modified Inorganic Binders Intended for 3D Printing on Selected Properties of Thermally Cured Moulding Sands – Conventionally and with Microwaves
(AGH University Press, 2026) Halejcio, Dawid M.; Major-Gabryś, Katarzyna
This study determined the impact of thermal curing on the basic properties of moulding compounds made with commercial inorganic binders and binders based on them, modified for use in 3D printing technology (Binder Jetting). Two inorganic binders based on sodium silicate and a binder based on aluminosilicates were tested. As part of the work, the parameters for thermal curing of the mixtures were selected: for curing in a dryer, the best properties were obtained for mixtures containing 2.0 p.p.w. of binder cured for 10 min at 160°C. In the case of microwave curing, the best properties were obtained for moulding sands containing 2.0 p.p.w. of binder cured for 6 min at a device power of 800 W. The tests showed that the basic properties of moulding compounds with binders developed on the basis of commercial binders for use in 3D printing technology, thermally cured in a dryer, do not differ significantly from the properties of compounds with commercial binders. In the case of microwave curing, a reduction in the strength of compounds with new binders was observed in relation to compounds with classic binders. Thermal deformation tests of compounds with classic and modified binders confirmed the typical behavior observed for inorganic systems. It was proven that new, modified inorganic binders developed for 3D printing of moulds and cores using Binder Jetting technology can be used as binding materials in thermally cured moulding sands. Both thermal curing methods were assessed as suitable for curing moulding compounds with new binders.
Access status: Open Access ,
Characteristics of wastes produced by polish ferrous alloys casting foundries between the years 2010-2014
(AGH University of Science and Technology Press, 2019) Skrzyński, Mateusz
The balance of wastes originating from the foundry processes of ferrous alloys, prepared on the basis of data made available by the Polish Central Statistical Office, is presented in this paper. The kind and amount of individual foundry wastes subjected to management and storage by foundry plants were analysed. The problem of wastes between the years 2010-2016 is discussed on the national scale, as well as in individual regions or voivodeships. Altogether, 27,375.9 tons of waste from the group no. 10, of which non-ferrous metal and ferrous alloy wastes from foundry plants constituted 2%, were produced in Poland in 2010. This situation remained at a similar level over successive years, till 2014. The positive prognosis constitutes the fact that the amount of waste stored on dumping grounds belonging to foundry plants in Poland is gradually decreasing. This may be related to increasing costs of waste storage. During the tested years, the annual amount of gathered waste decreased from 4,796.6 thousand tons (in 2010) to 4,477.6 thousand tons (in 2014).
Access status: Open Access ,
An evaluation of combustion kinetics for the synthesis reaction of the reinforcing phase during casting
(AGH University of Science and Technology Press, 2020) Wiktor, Tomasz; Sobula, Sebastian; Burbelko, Andriy A.; Ptasznik, Michał
The computer modeling of the solidification process in castings with local composite reinforcement (LCR) obtained as a result of in situ reactions of self-propagating high temperature synthesis (SHS) is difficult due to limited data on the thermo-physical parameters of exothermic effects and the kinetics of the synthesis reaction. In the present study, Hadfield cast steel casting was manufactured with LCR containing titanium carbide particles obtained in situ by the SHS method. Reaction kinetics of titanium carbide synthesis in the composite casting were determined on the basis of temperature measurements in the area of LCR during the process. For the estimation of the reaction, the Fourier Thermal Analysis method was used. The paper presents the results of temperature measurement and the results of the calculation of SHS reaction kinetics. It was found that the reaction time under the conditions of the analyzed casting is below 3 s.
Access status: Open Access ,
Study of AlSi7Mg0.6 alloy by selective laser melting - mechanical properties, microstructure, heat treatment
(AGH University of Science and Technology Press, 2019) Mauduit, Arnold; Gransac, Hervé; Auguste, Pierre; Pillot, Sébastien
This study presents a panorama of the AlSi7Mg0.6 (A357) aluminum alloy in additive manufacturing by selective laser melting. The document is mainly interested in the metallurgical tempers obtained after manufacture and after heat treatment, it quickly cover the process. The results concerning the material integrity (porosity), mechanical properties, microstructures, residual stresses, etc., are presented in order to best define the technological capacities of these metallurgical tempers: as-built, soft annealed, T6, and artificial aging. Some information on the mechanisms and kinetics of precipitation is also presented using the Johnson-Mehl-Avrami-Kolmogorov model. Finally, the conclusion proposes an inventory (advantages/disadvantages) of the metallurgical tempers obtained to better understand the industrial applications.
Access status: Open Access ,
Strength, water absorption, thermal and antimicrobial properties of a biopolymer composite wound dressing
(AGH University of Science and Technology Press, 2022) Chiosa Odili, Cletus; Sekunowo, Olatunde Israel; Ilomuanya, Margaret Okonawan; Gbenebor, Oluwashina Philips; Adeosun, Samson Oluropo
Conventional wound material allows bacterial invasions, trauma and discomfort associated with the changing of the dressing material, and the accumulation of body fluid for wounds with high exudate. However, there is a shift from conventional wound dressing materials to polymeric nanofibers due to their high surface area to volume ratio, high porosity, good pore size distribution, which allows for cell adhesion and proliferation. There is an urgent need to synthesis a biodegradable composite that is resistant to bacterial infection. In this study, an electrospun polylactide (PLA) composite suitable for wound dressing, with enhanced antimicrobial and mechanical properties, was produced. The neat PLA, PLA/CH (10 wt.%), PLA/CH (5 wt.%), PLA/CHS (10 wt.%), PLA/CHS (5 wt.%), PLA/CH (2.5 wt.%) /CHS (2.5 wt.%) and PLA/CH (5 wt.%)/CHS (5 wt.%), were electrospun using 0.14 g/ml solution. Results show that crystallinity (67.6%) of neat PLA declined by 3.8% on the addition of 2.5 wt.% chitin/chitosan with improved hydrophilicity of the composite. The tensile strength of neat PLA (0.3 MPa) increased (0.6 MPa) with 2.5 wt.% chitin/chitosan addition. The slight increase in the glass transition temperature from 75°C for neat PLA to 78°C of the composite fibre, showed improved ductility. The fibres showed little beads, hence suitable for wound dressing. The electrospun mats have good water absorption capacity and strong resistance against <i>Staphylococcus aureus</i>. Good performance was attained at 5 wt.% of chitin, chitosan and hybrid reinforcements. Therefore, a PLA/chitin/chitosan composite is recommended as a wound dressing material.
Access status: Open Access ,
New possibilities in thermal analysis of molding materials
(AGH University of Science and Technology Press, 2018) Svidró, Judit; Diószegi, Attila
Molding material-related studies within the research activities concerning foundry technology have always been limited despite the significant effect of molding mixtures on the quality of cast parts. One reason behind this trend is the difficulty in interpreting the results of such complex systems like molds and cores. This paper provides a new possibility for studying the heat-absorption performance of materials used as molding media in metal casting processes. By further developing the Fourier thermal analysis method of cores and molds introduced by earlier studies, the investigation of unbonded sand has become available. The heat-absorption properties of the components can be hereby separated and studied respectively. Thermal analyses were performed on sphere-shaped resin-bonded cores with various binder levels as well as on unbonded sand samples. The temperature data collected from two points of the samples were then used for the calculation of the novel thermophysical properties. The results revealed not only quantitative but qualitative differences in the characteristics of the binder decomposition processes, providing a deeper understanding on the thermal behavior of molding materials. The outcome of the research provides more accurate data, which is the key for the improved simulation of casting processes.
Access status: Open Access ,
Influence of structural characteristics on the mechanical properties of FDM printed PLA material
(AGH University of Science and Technology Press, 2020) Szczepanik, Stefan; Nikiel, Piotr
The present study reports on the influence of printing process parameters, architecture, raster, infill orientation and filling on the density, macrostructure, and mechanical properties, including impact resistance, of biodegradable polymer parts fabricated in polylactide (PLA) on a desktop printer. It complements and considers phenomenologically the results of recently published similar studies, including the use of recycled filament. In our study, complex mechanical properties for the samples printed at the same time on a Replicator 2 printer were investigated. Three samples were printed for each test. Full mechanical characteristics (tensile, compression and bend strengths and impact resistance) of the printed PLA material are reported. This is the novelty in comparison to other studies, where the samples test were printed individually or in a series for each test. The shape and thickness of the layered macrostructure, the presence of holes inside the layers, the number of shell perimeters and the fill density all influenced the tensile properties of the printed materials. These results show the possibility of printing with a 0.3, i.e. shorter printing time than 0.1, 0.15 and 0.18 mm layer thicknesses also reported, without significant decrease in mechanical properties. It is interesting to note that the compressive strengths, the yield of 70-80 MPa and a UTS 113-120 MPa for the printed material with a fill density of 94-96% are comparable with those of aluminum.
Access status: Open Access ,
Influence of the Addition of Tellurium and Heat Treatment on the Microstructure of Hypoeutectic White Cast Iron
(AGH University Press, 2025) Trela-Przybyło, Alicja; Kawalec, Magdalena; Górny, Marcin
This study investigates how the addition of tellurium and heat treatment affects the microstructure of hypoeutectic white cast iron that has been modified with alloying elements such as titanium, chromium and vanadium. Samples with different chemical compositions were prepared and subjected to a two-step heat treatment process. Microstructural characterisation was performed using optical and scanning electron microscopy. The results show that introducing tellurium significantly affects the morphology of the cementite and carbide phases, causing them to fragment and become more evenly distributed. Furthermore, heat treatment enhanced matrix refinement and promoted phase stability. The combination of tellurium addition and heat treatment produced the most favourable microstructures, characterised by the high dispersion of hard phases within a fine-grained matrix.
Access status: Open Access ,
The Circular Economy in Terms of Zinc Recovery from Industrial Waste – Directions for the Development and Profitability of Recycling
(AGH University Press, 2023) Bobrowski, Artur; Nejranowski, Aleksander
The article reviews the current state of the art in the field of zinc recycling. The results of model studies of the profitability (profitability) of the process of zinc recovery in precipitation in the form of dusts and sludges are presented. The cost of purchasing waste and the necessary energy and material expenditures were taken into account. It has been shown that access to a cheap source of waste is essential for the profitability of the zinc recovery proces.
Access status: Open Access ,
Influence of cooling rate on the structure and damping properties of the AlSi6Cu4 alloy
(AGH University Press, 2025) Piwowarski, Grzegorz; Ogrodnik, Mateusz
The investigated alloy was cast as a shaft into seven casting molds. Casting molds made of different materials were char acterized by different abilities to conduct heat from the sample. This property significantly influenced the cooling rate of the sample casting from the AlSi6Cu4 alloy. The highest cooling rate was achieved in a steel mold at 25°C and the lowest in a mold made of insulating mass. Different cooling rates significantly influenced the structure of the alloy. Different grain sizes were obtained and the morphology of the microstructure components changed. At the highest cooling rate of 16.63 K·s?1, a grain with an average size of 0.58 mm was obtained. However, in the mold with the lowest cooling rate of 0.36 K·s?1, the average grain size was 3.76 mm. Changes in the structure of the alloy also influenced its damping prop erties. The tested values f the vibration damping coefficient ? indicated that the AlSi6Cu4 alloy cooling with the highest cooling rate has the highest value of damping coefficient. This is influenced by the grain size and shape of the silicon pre cipitates. The refinement structure and fragmented components effectively disperse the vibration wave in the structure of the casting alloy.
Access status: Open Access ,
Deoxidation impact on non-metallic inclusions and characterization methods
(AGH University of Science and Technology Press, 2017) Nicoli, Cécile; Carton, Jean-François; Vaucheret, Alexis; Jacquet, Philippe
Deoxidation is an unavoidable step in the elaboration of steel. The study of its influence could improve the quality of low-carbon steel (0.20-0.25 wt.% of carbon). There are many deoxidation methods, and the most-common one consists of adding aluminum. Although it is a classic method, determining the optimal process parameters (quantity, yield, etc.) could be very sensitive. Deoxidation plays a determining role on inclusion cleanliness, especially on sulfide morphology. In order to control the efficiency of deoxidation, different techniques can be used. In this paper, an automated counting procedure on a scanning electron microscope with a field emission gun (FEG-SEM) is presented. This method was applied on samples cast in our laboratory under different deoxidation conditions. According to this, the resulting inclusion population is correlated with the aluminum content to find the optimal process parameters.